The standard measure of pancreatic enzyme replacement therapy (PERT) efficacy in treating exocrine pancreatic insufficiency (EPI) is the coefficient of fat absorption (CFA). CFA measurement involves 72-hour stool collection, which presents a logistical challenge because, although the test may be performed on an outpatient basis in clinical practice, hospitalization is needed if assurance of complete collection and 100% compliance is required, for example, in controlled situations such as clinical trials. Our aim was to investigate sparse stool sample collection as an alternative to complete 72-hour collection for measurement of stool fat in subjects with EPI.
Prospective data analysis from a previously published, double-blind, randomized, placebo-controlled, 2-period crossover trial in subjects ages 7 to 11 years with EPI caused by cystic fibrosis. Percentage fat (PF) data from sparse stool samples were compared with 72-hour CFA values as a dichotomous variable (<80%, ≥80%), with evaluation of sensitivity, specificity, and positive predictive value. Area under the curve values were obtained from receiver operating characteristic plots of sensitivity versus 1–specificity.
Twelve subjects provided samples for this analysis. Multiple-sample PF values ≤30% were greatly predictive for CFA values ≥80%, as shown by positive predictive value, sensitivity, and specificity values ≥0.89, with high accuracy (AUCs ≥0.93).
Sparse stool sampling for PF analysis appears to be a valid, practical alternative to 72-hour CFA determination and has potential as a screening tool in clinical practice to identify both suboptimal dosing in subjects with EPI receiving PERT and substantial fat malabsorption in subjects not receiving PERT.
*Abbott Products Inc, Marietta, GA
†Abbott Products GmbH, Hannover, Germany.
Address correspondence and reprint requests to Suntje Sander-Struckmeier, Abbott Products GmbH, Hans-Böckler-Allee 20, 30173 Hannover, Germany (e-mail: firstname.lastname@example.org).
Received 4 November, 2010
Accepted 7 June, 2011
This work was funded by Abbott Products Inc, Marietta, GA.
ClinicalTrials.gov number: NCT00690820.
S.C., D.B., and L.Z. were employees of Abbott, Marietta, GA, at the time of this analysis and writing of the manuscript. S.S.S. is an employee of Abbott, Hannover, Germany.